#ifndef _Tree_H_
struct TreeNode;
typedef struct TreeNode *SearchTree;
typedef struct TreeNode *Position;
#define ElementType int

SearchTree MakeEmpty(SearchTree T);
Position Find(ElementType X, SearchTree T);
Position FindMin(SearchTree T);
Position FindMax(SearchTree T);
SearchTree Delete(ElementType X, SearchTree T);
SearchTree Insert(ElementType X, SearchTree T);
ElementType Retrieve(Position P);
//删除数值最小的节点，并且返回其值
SearchTree DeleteMin(SearchTree T, ElementType *min);
void Print(SearchTree T);
#endif
struct TreeNode
{
    ElementType Element;
    SearchTree Right;
    SearchTree Left;
};
